Paving system with variable spacing between the pavers

ABSTRACT

A paving system for paving a surface area with pavers such that there are different sized spaces between some of the adjacent pavers. The paving system ( 10 ) has a substrate ( 12 ) with regularly spaced connectors ( 22 ) for attaching pavers ( 14 ) to the substrate. The pavers are of varying sizes such that the spaces ( 38   f ) between relatively smaller pavers ( 14   f ) are larger than the spaces ( 38   a ) between relatively larger pavers ( 14   a ). This permits the construction of a paved surface ( 32 ) having different permeability to water in different parts thereof.

FIELD OF THE INVENTION

The invention pertains to paving systems of the type that use individual pavers, and in particular to systems for paving a surface area with spaced-apart pavers.

BACKGROUND OF THE INVENTION

In some paving applications, it is desirable to place pavers (paving stones) with spaces between them in order that the paved surface will support pedestrians and vehicles, while still being permeable to water. For some of these applications, it is desirable to vary the spacing between pavers across the ground surface. Examples include roadways and driveways where it is desired to have both driveability and a specified overall permeability. Another example would be an area intended to serve as a transition between a footpath or driveway and a garden, in which some foot traffic will occur. Laying the pavers in a manner that forms such a paved but permeable surface is labor-intensive and difficult, in part because of the need for the non-abutting, spaced-apart pavers to be stable in the ground, and in part because of the difficulty of laying out and executing a design in which the spacing between pavers may be unequal.

SUMMARY OF THE INVENTION

The invention is a paving system for paving a surface area with pavers such that there are different sized spaces between some of the adjacent pavers, providing variation in the water permeability across the paved surface. The system can be readily laid out on the ground surface and assembled. The system includes a substrate that may be flexible, which facilitates laying pavers on varied and curved ground surfaces. This is difficult to do with prior art paving systems in which the pavers rely on neighboring pavers for support, and which can therefore accommodate only very gradual variations in contour. In the invention, the pavers are supported by the substrate rather than by adjacent pavers.

According to one aspect of the invention, there is provided a paving system having a substrate with pavers of a range of sizes. The spaces between adjacent pavers may be unequal in different sections of the paved surface, whereby the surface has different permeability to water in different sections.

According to another aspect of the invention, there is provided a paving system comprising a substrate and a plurality of pavers. The substrate has a plurality of spaced-apart attachment means, each attachment means being adapted for attachment to a respective paver. The plurality of pavers comprises two or more sets of pavers. A first set comprises pavers having a first top surface area and a second set comprises pavers having a second top surface area. The second top surface area is smaller than the first top surface area. The system may include one or more additional sets of pavers having different top surface means.

According to a further aspect of the invention, there is provided a paving system comprising a substrate and a plurality of pavers. The substrate has a plurality of spaced-attachment means adapted for attachment of the pavers to the substrate. The attachment means are arranged such that pavers are attachable with spaces between at least some adjacent pavers being larger in size than spaces between some other adjacent pavers.

According to a further aspect of the invention, there is provided a paving system comprising a substrate and a plurality of pavers. The substrate has a plurality of spaced-apart attachment means, each attachment means being adapted for attachment to a respective paver. The plurality of pavers comprises some pavers having different top surface areas from other pavers, some top surface areas being smaller than others. The attachment means are arranged such that the pavers are attachable with spaces between adjacent pavers having smaller top surface areas being larger than the spaces between adjacent pavers having larger surface areas.

According to a further aspect of the invention, there is provided a paving system comprising a substrate on a ground surface and a plurality of pavers attached to the substrate. The substrate has a plurality of spaced-attachment means, each paver being attached to a respective attachment means. The plurality of pavers comprises some pavers having different top surface areas from other pavers, some top surface areas being smaller than others. The pavers have spaces therebetween such that the spaces between adjacent pavers having smaller top surface areas are larger than the spaces between adjacent pavers having larger surface areas.

According to a further aspect of the invention, there is provided a paving system comprising a substrate on a ground surface and a plurality of pavers attached to the substrate. The substrate has a plurality of spaced-apart attachment means, each paver being attached to a respective attachment means. The plurality of pavers comprises two or more sets of pavers. A first set comprises pavers having a first top surface area, and a second set comprises pavers having a second top surface area. The second top surface area is smaller than the first top surface area. The pavers have spaces therebetween such that the spaces between adjacent pavers of the second set are larger than the spaces between adjacent pavers of the first set. The system may include one or more additional sets of pavers having different top surface areas.

Further aspects of the invention and features of specific embodiments are described below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a first embodiment of the invention, showing the paving system partly assembled.

FIG. 1A is a close-up view of a portion of the substrate and a paver of FIG. 1.

FIG. 2 is a top plan view of the paving system of FIG. 1, fully assembled to form a paved surface of varying permeability.

FIG. 3 is a close-up view of a portion of a substrate and paver according to a second embodiment of the invention.

FIG. 4 is an isometric view of a third embodiment of the invention, showing the paving system partly assembled.

DETAILED DESCRIPTION

Throughout the following description and in the drawings, corresponding and like parts are identified by the same reference characters.

Referring first to FIGS. 1, 1A and 2 which show one embodiment of the invention, the paving system 10 comprises a substrate 12 and pavers 14 that are attached to the substrate in fixed positions. The substrate is a geogrid 12 comprising a web of longitudinal and transverse strips 16 with a regular pattern of openings 18. On one face of the geogrid, being the upper face 20 when the geogrid is laid on a ground surface, there is a plurality of projections 22 that are the means for attaching the pavers 14 to the substrate. The projections 22 are located in fixed positions on the upper face of the geogrid, equidistantly spaced from adjacent projections and forming a regular pattern across the face of the substrate. Alternatively, the projections may be arranged in other patterns in which the spacing is not equidistant.

The substrate 12 is preferably a flexible sheet, enabling it to conform to ground surfaces that are not flat. In other embodiments, the sheet may be a geotextile or other geosynthetic, or other plastic or highly durable material. The substrate should be permeable to water so that rainwater or other surface water can pass through it into the ground. For the geogrid substrate, this function is provided by the openings 18.

The projections 22 are integral with the geogrid 12, being formed thereon by extrusion during the manufacturing process and comprising the same polymer material as the geogrid. The geogrid 12 may be made by extruding a sheet, passing it between rollers to form the projections 22, and punching out the openings 18. The sheet may also be made by means of vacuum forming or injection molding. Alternatively, the projections may be separate pieces that are affixed to the geogrid after it is formed.

In the illustrated embodiment, the projections 22 have an oval-shaped footprint on the geogrid. Alternatively, the projections may have a footprint that is rectangular, cross-shaped or other shapes. Footprint shapes other than round are preferred in order to prevent rotation of the pavers, for embodiments in which each attachment means is a single projection.

The pavers 14 may be made of any suitable material, including stone, concrete, brick, plastic, rubber and wood. In the illustrated paving system 10, the pavers are cylindrical, being round in top plan view, but alternatively they can be of any suitable shape, including hexagonal, square, rectangular, etc. The pavers have a top surface 24, a bottom surface 26 and a side wall 28. The side wall is orthogonal to the top and bottom surfaces. Alternatively, the side wall may be sloped or stepped, such that the top surface is either smaller or larger than the bottom surface. A recess 30 in the bottom center of each paver is of a size and shape for mating engagement with a projection 22. When a paver is placed onto the geogrid with the recess 30 aligned with a projection 22, the projection fits snugly into the recess with the bottom surface 26 of the paver in contact with the upper surface 20 of the geogrid. The paver is thus held in a fixed position on the geogrid, centered on the projection. The paver can be lifted off the projection, which may be useful during the process of constructing the paved surface. In effect, the projection acts as a registration pin, to assign a position for the paver on the substrate and hold it there against lateral movement.

The pavers and the projections can be of any sizes suitable for a particular application. By way of example, the paver projections may be spaced 8 inches (20.3 cm) apart (center to center), arranged in a staggered array as illustrated in FIGS. 1 and 2, and the pavers may be circular with a diameter from 3 inches (7.6 cm) to 8 inches (20.3 cm), a thickness of 3 inches (7.6 cm) with the projections being 2 inches (5.1 cm) long and 1 inch (2.54 cm) wide at their base and 1 inch (2.54 cm) in height.

The pavers used in the paving system 10 are of a range of sizes in order that the paved surface formed by the system has varying spacing between pavers, and thus varying water permeability, in different areas thereof. Referring to FIG. 2, an embodiment of the paving system is shown in which there are six sets of pavers 14 a, 14 b, 14 c, 14 d, 14 e and 14 f. The pavers of set 14 a are largest in diameter, and therefore largest in top surface area, and substantially abut each other. They form the three staggered rows of pavers adjacent to a first edge 34 of the paved surface 32. The pavers of set 14 f are the smallest in diameter, and therefore have the smallest top surface areas. They form the four staggered rows of pavers adjacent to a second, opposite edge 36 of the paved surface. The pavers of sets 14 b-14 e are of graduated intermediate sizes. Each set forms two or more staggered rows of pavers extending between the edges 34, 36 of the paved surface 32.

Since each paver is centered on a projection 22 which is equidistant from adjacent projections, the centers of the pavers are likewise equidistant from the centers of the adjacent pavers. The pavers of set 14 f, being the smallest, have the largest distances between adjacent pavers of that set and accordingly the largest spaces 38 f between adjacent pavers. The pavers of set 14 a substantially abut at their periphery and have only small spaces 38 a between them; and the spaces between adjacent pavers of each intermediate set increase in size in the direction from first edge 34 to the second edge 36 of the paved surface 32, such that the spaces increase in the order 38 a, 38 b, 38 c, 38 d, 38 e and 38 f. In use, the spaces between the pavers are filled with water-permeable material, such as soil, sand or gravel (not shown in FIG. 2 for clarity of illustration), and, accordingly, the permeability of the paved surface 32 varies as between the areas defined by each set of pavers, increasing in the direction from the area of set 14 a to the area of set 14 f, which has the highest permeability.

A paved surface 32 is created using the paving system 10 by laying the substrate 12 on a suitably-prepared ground surface, with the projections 22 facing upward. The pavers are then attached to respective projections, arranging pavers of selected sizes to form the desired pattern of spacing between adjacent pavers. The spaces are then filled with soil or other water-permeable fill material. In some applications, grass, moss or other plant material will be planted in the spaces.

In other embodiments of the paving system, instead of a single projection 22 for attaching each paver, there may be two or more projections that together comprise an attachment means for holding a paver in position. In such case, the paver has the corresponding two or more recesses required for mating engagement with the projections. Increasing the number of projections that together comprise an attachment means on the substrate decreases the forces on each projection that are caused by use of the paved surface, in particular by vehicles. An example of such embodiment is illustrated in FIG. 3, which shows a portion of a geogrid substrate 112 in which each attachment means comprises a set 121 of seven projections 122. Each set 121 is spaced from adjacent sets in the same manner that, in the embodiment of FIG. 1, the individual projections 22 are spaced apart. Each paver 114 has a set of recesses 130 arranged to engage the projections 122 of a set 121. Accordingly, each paver is held by a respective set 121 of projections.

In other embodiments of the invention, the pavers may be of equal size and variation in the distances between pavers, or in the permeability of the paved surface, is accomplished by attaching the pavers to the substrate at varying distances apart. Referring to FIG. 4, showing a further embodiment of the invention, the paving system 200 comprises a geogrid substrate 212 having a regular pattern of openings 18 and with rows 221 of projections 222 for attaching the pavers 214. The rows 221 are spaced a fixed distance apart. Within a row 221, the projections 222 are regularly spaced for mating engagement with recesses 230 in the pavers. The projections 222 within each row 221 are arranged such that a paver can attach to the substrate in a plurality of different positions along a row 221, and thus at different distances from an adjacent paver attached on the same row. For example, as seen in FIG. 4, a paver 214 a is separated from one adjacent paver 214 b by one distance 215, and from a second adjacent paver 214 c by a second, smaller distance 217. As between rows, adjacent pavers are at a fixed distance apart; in the illustrated paving system 200, this fixed distance is minimal, the pavers virtually abutting against the pavers in adjacent rows. Alternatively, larger spaces may be provided between pavers in adjacent rows by increasing the distance between adjacent rows 221 of projections 222, or by using narrower pavers.

As will be apparent to those skilled in the art, many modifications and alterations are possible in the practice of the invention without departing from the scope thereof. For example, other means of attaching the pavers to the substrate can be employed. Rather than the substrate having projections and the pavers having recesses, the substrate may have openings configured to receive projections on the bottom side of the pavers. Such projections could be integral to the pavers or could be separate pieces that are attached thereto. Or, the substrate can have openings and the pavers can have recesses, and pins are inserted in both to attach the substrate and pavers together. Various other mechanical arrangements to attach pavers to a substrate can be used. Accordingly, the scope of the invention is to be construed in accordance with the following claims. 

1. A paving system comprising: a substrate and a plurality of pavers; the substrate having a plurality of spaced-apart attachment means, each attachment means being adapted for attachment to a respective paver; the plurality of pavers comprising some pavers having different top surface areas from other pavers, some top surface areas being smaller than other top surface areas; the attachment means being arranged such that the pavers are attachable with spaces between adjacent pavers having smaller top surface areas being larger than the spaces between adjacent pavers having larger surface areas.
 2. A paving system according to claim 1, wherein the plurality of pavers comprises two or more sets of pavers, a first set comprising pavers having a first top surface area and a second set comprising pavers having a second top surface area, the second top surface area being smaller than the first top surface area.
 3. A paving system according to claim 2, wherein the plurality of pavers further comprises a third set of pavers having a third top surface area, the third top surface area being smaller than the second top surface area.
 4. A paving system according to claim 1, wherein the attachment means are arranged such that each attachment means is equidistant from the attachment means that are adjacent thereto.
 5. A paving system according to claim 1, wherein the paving system is arranged on a ground surface and the pavers are attached to the substrate with the spaces between adjacent pavers having smaller top surface areas being larger than the spaces between adjacent pavers having larger surface areas.
 6. A paving system according to claim 1, wherein each attachment means comprises a projection adapted to engage in a recess in a respective paver.
 7. A paving system according to claim 1, wherein each attachment means comprises two or more projections adapted to engage in recesses in a respective paver.
 8. A paving system according to claim 1, wherein each attachment means comprises one or more recesses adapted to receive one or more projecting members on a respective paver.
 9. A paving system according to claim 1, wherein each paver has one or more recesses for engagement with the attachment means.
 10. A paving system according to claim 1, wherein the substrate is a porous flexible sheet.
 11. A paving system according to claim 1, wherein the substrate is a geosynthetic.
 12. A paving system according to claim 1, wherein the substrate is a geogrid.
 13. A paving system according to claim 1, wherein the pavers are of the same shape.
 14. A paving system according to claim 13, wherein the shape is one of round, hexagonal, octagonal, rectangular and square.
 15. A paving system according to claim 1, wherein the pavers comprise one of stone, concrete, brick, plastic, rubber and wood.
 16. A paving system according to claim 5, further comprising a water-permeable fill material in the spaces between the pavers.
 17. A paving system according to claim 1, wherein the substrate is a flexible sheet. 18.-32. (canceled) 